@article{BUMI_1952_3_7_4_a1,
     author = {Graffi, Dario},
     title = {Sul problema della derivata obliqua.},
     journal = {Bollettino della Unione matematica italiana},
     pages = {378--382},
     publisher = {mathdoc},
     volume = {Ser. 3, 7},
     number = {4},
     year = {1952},
     zbl = {0047.34304},
     mrnumber = {53292},
     language = {it},
     url = {http://geodesic.mathdoc.fr/item/BUMI_1952_3_7_4_a1/}
}